Bedspring



Feb. 11, 1941.

W. E. WUNDERLICH BEDSPRING Filed Jan. 30, 1939 INVENTOR. 7451/14/15fi/rpaez 1:6

ATTORN E YE Patented Feb. 11, 1941 1 I arms BEDSPRING WilliamWunderlich, Muncie, Ind., assignor to The Moore Company, Muncie, Ind., acorporation of Indiana Application January so, 1939, Serial No. 253,5364 Claims. (01. 5- 2e0) My invention relates to spring units orassemblies of the type embodied in inner-spring mattresses,seat-cushions, etc. Such assemblies embody a plurality of rows ofgenerally helical compression springs having their end turns flexiblyinterconnected to maintain the springs in proper relative positions, theupper and lower end turns of the springs along the margins of theassembly being secured respectively to upper and lower border frames.

My invention relates particularly to that type of spring assembly inwhich the border frame is of flat stock, and has for its principalobject the interconnection of the border frames with the marginal springturns in such a way that each of such spring turns will be locateddefinitely in the plane of the border frame but will still possess acertain freedom of angular movement about the border frame as an axis.

In carrying out my invention I provide the end turns of marginalcompression springs with outwardly olfset portions which overlap theborder frame, and on each side of the border frame I dispose a helicalspring which closely surrounds the border frame and several turns ofwhich embrace each of such offset portions. In addition, I provide eachof the offset portions with a supplementary offset which is disposedoutside of the helical spring and between which and the outer edge ofthe border frame one turn of the helical spring extends.

The accompanying drawing illustrates my invention: Fig. 1 is afragmental plan View of a corner of a spring assembly with a portion ofthe upper border frame broken away to show the lower border frame; Fig.2 is a fragmental view similar to Fig. 1, but on an enlarged scale; andFig. 3 is a section on the line 3-3 of Fig. 2.

As will be clear from Fig. 1, the spring assembly constitutes aplurality of rows of generally helical compression springs II]. In theinterior of the assembly, the end turns of adjacent springs of each roware provided with offsets H which extend into overlapping relation andare embraced by helical springs l2 extending transversely of the rows ofcompression springs in a conventional manner. The assembly is providedwith upper and lower border frames I3 and M which extend completelyaround the assembly and to which the end coils of adjacent springs aresecured.

As is clear from Fig. 3, I make each of the border frames of fiat stockbent in its own plane to conform to the margin of the assembly. Each endturn of each compression spring at the margin of the assembly isprovided with an outwardly extending offset portion l5 which overlapsthe border frame l3, as indicated in Fig. 2. Each offset portion I5 isprovided with a supplementary offset [6 which is disposed between theends of 5 the offset l5 and which extends outwardly beyond theouter edgeof the border frame.

The end turns of the compression springs at the margin of the assemblyare secured to the border frame by means of helical springs ll closely,surrounding the material of the border frame and extendinglongitudinally thereof. One turn of the helical spring ll extendsthrough the supplementary offset [6 of each of the compression springs,such helical spring-turn passing between the offset 16 and the outeredge of the border frame l3, as indicated at IS in Figs. 2 and 3. Theoffset [5 is so proportioned as to be embraced by one or more turns ofthe helical spring I! on each side of the offset l6. To avoid distortionof the helical spring ll it may be necessary to locate the supplementaryoffset 6 a short distance to one side of the center of the main ollsetl5, as shown in Fig. 3. Desirably, each of the supplementary offsets ithas a radial depth such that when the material of the helical spring llpasses between it and theouter edge of the border frame I3, the portionsof the offset IE3 at each side of the supplementary offset IE will beapproximately flush with the outer edge of the border frame.

By the construction described, the end turns of the compression springsat the margin of the assembly are definitely located along the borderframe. Inward movement of the spring turn relative to the border frameis prevented by the presence of a helical-coil within the supplementaryoffset l6; outward movement is prevented by the helical-coils whichembrace the body of the main offset l5; and movement longitudinally ofthe border frame is prevented by engagement of the sides of thesupplementary offset with the helical-coil passing through it. However,since the points of contact between the helical spring l7 and the oifsetportions 15 and 6 are all located adjacent the outer edge of the borderframe l3, each end turn of each compression spring possesses a certainfreedom of angular movement relative to the border frame about the outeredge of the border frame as an axis. Because of this limited freedom ofangular movement, the spring assembly possesses along its edges asomewhat higher degree of flexibility than if all movement between theborder frame and the spring-turns overlapping it were prevented.

I claim as my invention:

1. In a spring assembly having a plurality of rows of compressionsprings, a border frame of fiat stock surrounding said assembly in theplane of the end turns of said springs, each of the end turns adjacentsaid frame being provided with an outwardly offset portion overlappingsaid border frame, an outwardly extending supplementary offset on eachof said main ofiset portions, and a helical spring embracing said borderframe and having three adjacent turns associated with each of saidoffset portions, the middle one of' rows of compression springs, aborder frame of flat stock surrounding said assembly in the plane of theend turns of said springs, each of the end turns adjacent said framebeing provided with an outwardly offset portion overlapping said borderframe, an outwardly extending supplementary ofiset on each of said mainofiset portions, and a helical spring embracing said border frame andhaving three adjacent turns associated with each of siad offsetportions, the middle one of said three turns passing through thesupplementary offset between it and the outer edge of the border frameand the other two turns embracing the main ofiset portion on oppositesides of the supplementary offset and holding such main offset portionagainst the face of the border frame.

3. The invention set forth in claim 1 with the addition that saidsupplementary offset is displaced from the center of the main offsetportion.

4. The invention set forth in claim 2 with the addition that saidsupplementary offset is displaced from the center of the main offsetportion.

WILLIAM E. WUNDERLICI-I.

